Saved in:
Bibliographic Details
Main Authors: Brutsche, Johannes, Riepl, Lukas
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.25668
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917444076961792
author Brutsche, Johannes
Riepl, Lukas
author_facet Brutsche, Johannes
Riepl, Lukas
contents Based on discrete observations, we develop a test to infer if the volatility function $σ(\cdot)$ within the nonparametric Gaussian white noise model $dY_t = σ(t)dW_t$ is constant. The testing procedure is shown to be minimax-optimal and adaptive for infill asymptotics and these results entail that a deviation from the null hypothesis of constancy is best measured in terms of the ratio of $σ(t)$ and its $L^2$-average. The derivation of optimal constants requires the construction of hypotheses with height $h(b)$, where the parameter $b$ solves $F_n(b)=0$ for given functions $F_n$. Proving this equation to be solvable for each $n\in\mathbb{N}$ and establishing quantitative bounds of the solutions is built upon the implicit function theorem.
format Preprint
id arxiv_https___arxiv_org_abs_2604_25668
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Sharp adaptive nonparametric testing for constant volatility
Brutsche, Johannes
Riepl, Lukas
Statistics Theory
Based on discrete observations, we develop a test to infer if the volatility function $σ(\cdot)$ within the nonparametric Gaussian white noise model $dY_t = σ(t)dW_t$ is constant. The testing procedure is shown to be minimax-optimal and adaptive for infill asymptotics and these results entail that a deviation from the null hypothesis of constancy is best measured in terms of the ratio of $σ(t)$ and its $L^2$-average. The derivation of optimal constants requires the construction of hypotheses with height $h(b)$, where the parameter $b$ solves $F_n(b)=0$ for given functions $F_n$. Proving this equation to be solvable for each $n\in\mathbb{N}$ and establishing quantitative bounds of the solutions is built upon the implicit function theorem.
title Sharp adaptive nonparametric testing for constant volatility
topic Statistics Theory
url https://arxiv.org/abs/2604.25668